Toyota Camry Hybrid AHV40 Manual page 229

Heated Oxygen Sensor and Air Fuel Ratio Sensor
1) General
D The heated oxygen sensor and the air fuel ratio sensor differ in output characteristics.
D The output voltage of the heated oxygen sensor changes in accordance with the oxygen concentration
in the exhaust gas. The THS ECU uses this output voltage to determine whether the present air-fuel
ratio is richer or leaner than the stoichiometric air-fuel ratio.
D Approximately 0.4 V is constantly applied to the air-fuel ratio sensor, which outputs an amperage that
varies in accordance with the oxygen concentration in the exhaust gas. The THS ECU converts the
changes in the output amperage into voltage in order to linearly detect the present air-fuel ratio.
OX1B
Heated
Oxygen
Sensor
O1B-
Heated Oxygen Sensor Circuit
A/F Sensor
Output (V)*
*: This calculation value is used internally in the THS ECU, and is not an THS ECU terminal voltage.
ENGINE - 2AZ-FXE ENGINE
Air Fuel
THS ECU
Ratio Sensor
4.2
2.2
14.7
11 (Rich)
Air Fuel Ratio
A1A+
(3.3V)
THS ECU
A1A-
(2.9V)
Air Fuel Ratio Sensor Circuit
: Air Fuel Ratio Sensor
: Heated Oxygen Sensor
1
Heated Oxygen
Sensor Output (V)
0.1
19 (Lean)
D13N11
EG-41
02HEG56Y